A TOP-level inquiry is under way within Merseyside Police to try and establish how previously unreleased pictures of James Bulger's killers were given to the media.

Senior officers in the force were said to be "livid" after the images, taken just hours after the pair's arrest, were published yesterday.

The pictures were not formally released by the force, meaning that someone has almost certainly made, or been given copies of the photographs, in total disregard of official policy.

Normally, permission for pictures taken of suspects at the time of arrest has to be given by the senior investigating officer in a case before they can be released.

But that did not happen regarding these latest pictures of Robert Thompson or Jon Venables.

Last night, the assistant chief constable of Merseyside Police, Grahame Barker said: "These pictures, taken in 1993, have never been officially released by the force.

"And an internal inquiry has been launched to find out how these pictures were disclosed."

The images were broadcast during a television documentary on Tuesday night which examined the proposed release of Thompson and Venables.

The pair were just ten years old when they abducted the two-year-old from a north Merseyside shopping centre, leaving his battered body on a railway line just a couple of miles away, where it was subsequently cut in two by a passing train.

Next week, solicitors representing both boys will take their cases to a Parole Board hearing where it is widely expected their release will be recommended.

However, even if this does occur, neither Thompson nor Venables will be freed completely.

Both will be sent to a "halfway house" where, over a period of months, they will be helped to rehabilitate back into society almost eight years after they were ordered to be detained at Her Majesty's Pleasure.

Last night, sources close to the case dismissed as "pure speculation" claims either boy could be freed within days of their appearing before the Parole Board next week.

Yesterday, a charity opposed to the boys' release announced their intention to hold a protest vigil outside the Parole Board headquarters in London.

Mothers Against Murder and Aggression (MAMA) was formed followed James' death in February 1993.

Co-founder Lynn Costello said: "We have taken hundreds of phone calls from people who think that it is disgusting that they are thinking of letting the killers out.

"I do not think that they have been rehabilitated. We need to see proof. It will be a completely peaceful protest. It is also a vigil for James."

However, a spokesman for the Justice for James group, set up to help the victim's mother, Denise Fergus, raise money to fight the proposed release said they would not be involved in the protest.

He added: "We are aware of the vigil but we do not intend to take part.

"That is not to say we do not understand why they want to make their feelings known because James' killers simply have not been properly punished.

"Denise is hoping the Parole Board will make the right decision and keep them in custody."